Blood Coagulation Tests Hematology 6 Blood Coagulation Tests Lee Woo In, MD, PhD Department of Laboratory Medicine

Homeostasis (항상성) Procoagulant Regulatory Endothelium Coagulation proteins Platelets

NL Endothelial Cell : Anti-thrombotic state -항혈소판, -항응고, -섬유소용해 Damaged Vessel : Thrombotic state Platelet activation Adhesion Prothrombotic

Primary Hemostasis Platelet plug :key Function of platelet 혈관수축 혈소판 adhesion, aggregation 작은 혈관손상의 지혈 Function of platelet Adhesion Release Aggregation Coagulant activity

Secondary Hemostasis Fibrin clot :key 응고인자 활성화 큰 혈관손상 견고한 haemostatic plug

Three factors for Hemostasis Vascular factors local vasoconstriction (immediate reaction) compression of injured vessels by blood extravasated into surrounding tissues Platelet factors adhere to the site & form aggregates (hemostatic plugs) release factors to augment vasoconstriction vessel wall repair (platelet-derived growth factor) Plasma factors

Plasma Coagulation factors Factor I: fibrinogen Factor II: prothrombin Factor III: tissue thromboplastin (tissue factor & phospholipid) Factor IV: ionized calcium Factor V: occasionally called labile factor or proaccelerin Factor VI: unassigned Factor VII: occasionally called stable factor or proconvertin Factor VIII: anti-hemophilic factor Factor IX: plasma thromboplastin component, Christmas factor Factor X: occasionally called Stuart-Prower factor Factor XI: occasionally called plasma thromboplastin antecedent Factor XII: Hageman factor Factor XIII: fibrin-stabilizing factor

Coagulation Cascade Intrinsic pathway Extrinsic pathway

Regulatory mechanisms Normally prevent activated coagulation reactions local thrombosis or DIC Antithrombin III, protein C, protein S, etc Fibrinolytic system Plasmin-plasminogen system etc

Coagulation Tests Tests for Hemostatic plug(Primary hemostasis) Bleeding time Vessel contraction & primary hemostasis 혈소판질환, 폰빌레브란트 병 Platelet count Platelet function test 1) Adhesion test … vWD, Bernard Soulier, uremia

2) Aggregation test ; ADP, collagen, thrombin, epinephrine, ristocetin  응집률, 속도 3) 혈소판 기능과 아스피린 저항성 검사

Tests for fibrin plug (2ndary hemostasis) 1. Prothrombin time(PT) 환자혈장 + tissue thromboplastin + 칼슘 Factor VII activation Fibrin clot 시간 측정 I, II, V, VII, X 인자(NL 30%이어도 PT 정상) Report 단위: sec, %, INR INR : Vit K dependent factor(II, VII, IX, X) 길항제인 coumarin(warfarin) 복용 환자의 치료 농도 monitoring에 이용 INR(international normalized ratio)= (환자의 PT/참고치 PT)ISI (internaltional sensitivity index) Therapeutic range 2 ~ 3

2. aPTT 3. Mixing test(혈장혼합검사) Factor XII, XI 응고인자에 대한 활성제(kaolin, ellagic acid, celite), 혈소판 대용 물질인 인지질 첨가 VIII, IX, X, XII, prekallikrein, HMWK I, II, V, X은 공통 이나 문제 발생하면 PT가 연장 헤파린 오염 헤파린 치료(정상 aPTT의 1.5 ~ 2.5배) LMWH, 헤파린유사 항응고제 등은 anti-Xa법으로 검사 lupus anticoagulant 3. Mixing test(혈장혼합검사) 감별 : 응고인자 결핍 vs. 응고억제인자 정상범위로 교정되면 응고인자 억제인자, anti-phospholipid ab.,anti-prothrombin

4. Activated clotting time(ACT) 5. Thrombin time aPTT와 유사, ,헤파린 치료 모니터링 5. Thrombin time Hypofibrinogenemia, 섬유소기능이상, 과섬유소원증, 섬유소로 전환되는 것을 억제하는 인자 여부(헤파린, FDP) 6. Fibrinogen Acute phase reactant DIC, 간질환, 혈전용해치료 등에서 증가 7. Coagulation factor assay 8. von Willebrand factor subendothelial cell, megakaryocyte에서 생성되어 platelet adhesion - factor VIII 과 복합체를 이루며 순환 - Ristocetin cofactor assay … vWF의 기능 검사 - Ristocetin에 의한 혈소판응집정도 혈장의 vWF의 활성도와 비례

Laboratory markers of Fibrinolysis Fibrin clot이 다시 용해되는 과정 Key : plasmin

FDP test ( fibrinogen/fibrin degradation product) ; 섬유소용해 선별검사 DIC screening, hyperfibrinolysis, thromboembolic disease 증가 D-dimer fibrin clot이 있었음을 의미 섬유소용해 확진 검사 (-): thrombosis 진단을 배제 Plasminogen Alpha-2 antiplasmin

Acquired inhibitor VIII 응고인자 항체 Lupus anticoagulant VIII 응고인자 일정량을 불활성화 시키는 inhibitor activity Pt plasma + Normal plasma residual activity of factor VIII 측정 1 Bethesda unit: 1mL내의 응고억제인자가 응고인자 VIII 활성도를 50% 로 감소시키는 양 Lupus anticoagulant 항인지질 항체(antiphospholipid antibody, APA)의 일종 자가면역성, 동종면역성 면역글로블린 Antiphospholipid Antibody SLE, autoimmune disease, lymphoprolierative disease Anticardiolipin antibody

Natural Anticoagulants Anti-thrombin Factor Xa, thrombin 억제 Heparin에 의해 활성도 증가 유전,간질환,DIC,oral contraceptive, preeclampsia Protein C Thrombin에 의해 활성화, factor Va, VIIIa을 억제 Protein S Protein C의 coenzyme -2 macroglobulin, heparin cofactor II Thrombin 억제

Tests for Hypercoagulation states 1.유전성 혈전성향의 원인 Natural anticoagulant 기능소실 응고인자의 기능항진 2.복합적 요인에 의한 과응고 상태 3.후천적 과응고 상태 Tests Primary antithrombin activity C protein activity S protein antigen activated protein C resistance Lupus anticoagulant Anticardiolipin Ab Secondary Leiden V 인자 prothrombin G20210A fibrinogen, homocysteine, factor VIII